pgsql: Count locked pages that don't need vacuuming as scanned.

Count locked pages that don't need vacuuming as scanned.

Previously, if VACUUM skipped vacuuming a page because it's pinned, it
didn't count that page as scanned. However, that meant that relfrozenxid
was not bumped up either, which prevented anti-wraparound vacuum from
doing its job.

Report by Миша Тюрин, analysis and patch by Sergey Burladyn and Jeff Janes.
Backpatch to 9.2, where the skip-locked-pages behavior was introduced.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/4c697d8f4845823a8af67788b219ffa4516ad14c

Modified Files
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src/backend/commands/vacuumlazy.c |    1 +
1 file changed, 1 insertion(+)